Differences Between Compressors for New Energy Vehicles and Traditional Fuel Vehicles

Difference Between The Two Types Of Compressors

Traditional fuel vehicles generally use a mechanical compressor. The compressor is powered by the engine. The compressor is connected to the engine by a belt, and the engine drives the compressor to operate. This type of compressor has the advantages of simple structure, low production and maintenance costs, and large cooling capacity. Its disadvantage is that it requires power from the engine, which reduces engine power.

The swash plate compressor used in traditional fuel vehicles consists of components such as suction plate, pulley, electromagnetic clutch, front cover, drive shaft, bearing, swash plate, wedge drive plate, piston, cylinder body, valve body, valve plate, control valve, rear cover and fixing bolts. The operation noise of the compressor mainly includes three types: mechanical noise, aerodynamic noise and electromagnetic noise.

New energy vehicles usually use an electric compressor. The working principle of the electric compressor for new energy vehicles is that the power battery supplies power to the compressor inverter. The inverter converts direct current into alternating current and outputs alternating current to the three-phase permanent magnet synchronous motor. The three-phase permanent magnet synchronous motor drives the scroll compressor to operate and compresses the low-pressure gaseous refrigerant into high-pressure gas.

New energy vehicles use a scroll compressor. This compressor cancels the front drive wheel, adds a drive motor and a separate control module, and uses refrigerant gas to compress the refrigerant. The core components of the scroll compressor include two intermeshing scrolls, which achieve high efficiency, low noise, reliability and energy saving. It is widely used in new energy electric vehicles.

The difference between the compressor for fuel vehicles and the compressor for electric vehicles lies in their different power sources. The compressor for fuel vehicles is usually driven by the engine, while the compressor for electric vehicles is powered by batteries. This means the compressor for electric vehicles does not produce emissions because it does not require fuel combustion. In addition, the noise of the compressor for electric vehicles is much lower than that of the compressor for fuel vehicles.

When the temperature inside the vehicle exceeds the set temperature, the vehicle air conditioning compressor will keep working. For new energy vehicles, since the electric compressor can operate at a high pressure ratio, it can change the effective compression stroke by means of a slide valve and perform stepless cooling capacity adjustment from 10% to 100%. It can adjust the speed at any time according to temperature demand to save energy, while the compressor for traditional vehicles cannot realize these functions. If it is a variable displacement compressor, it can adjust the displacement and also reduce the overall vehicle energy consumption.

The power of the compressor for traditional fuel vehicles mainly comes from the engine. The engine drives the compressor to operate through a belt. When the air conditioner is not turned on, the pulley of the compressor idles. After the air conditioner is turned on, the electromagnetic clutch is energized to connect the compressor pulley with the internal piston, so that the engine provides power for it.

This method increases the engine load and fuel consumption when the air conditioner of the fuel vehicle is turned on. Driving the compressor requires connecting the compressor pulley with the crankshaft of the internal combustion engine through a belt. Hundreds of kilograms of force are required to push the refrigerant to flow in the pipeline, and this power needs to be converted by fuel consumption.

In the medium and low speed range, the engine power output is low. After turning on the air conditioner, part of the engine power is used to drive the compressor, resulting in reduced power and affected acceleration efficiency.

Advantages And Disadvantages Of The Compressor For Traditional Fuel Vehicles

New Compressor Is Batteries

The compressor for new energy vehicles is usually powered by batteries. For example, the electric compressor of a new energy vehicle is powered by the power battery to the compressor inverter. The inverter converts direct current into alternating current and outputs alternating current to the three-phase permanent magnet synchronous motor. The three-phase permanent magnet synchronous motor drives the scroll compressor to operate.

Different from traditional fuel vehicles, the compressor for new energy vehicles does not rely on engine power, so it will not affect engine power.

The working principle of the electric compressor for new energy vehicles is: the power battery supplies power to the compressor inverter, the inverter converts direct current into alternating current and outputs alternating current to the three-phase permanent magnet synchronous motor, and the three-phase permanent magnet synchronous motor drives the scroll compressor to operate.

The core components of the scroll compressor include a fixed scroll and an orbiting scroll. The two scrolls with functional equation profiles are intermeshed and installed with a 180° stagger. When the drive motor rotates to drive the orbiting scroll to revolve, refrigerant gas is sucked into the outer part of the fixed scroll through the filter element.

As the drive shaft rotates, the orbiting scroll moves along a track inside the fixed scroll, forming six chambers between the orbiting and fixed scrolls with gradually decreasing volume from outside to inside. The refrigerant gas is gradually compressed in the six crescent-shaped compression chambers formed by the orbiting and fixed scrolls, and finally the compressed refrigerant gas is continuously discharged from the central hole of the fixed scroll through the valve plate.

The core components of the scroll compressor used in new energy vehicles include two intermeshing scrolls: one fixed scroll (fixed on the frame) and one orbiting scroll (directly driven by the motor to revolve around the fixed scroll with a small turning radius). Since they have the same profile, they are combined with a 180° phase difference.

In addition, the drive motor adopts a three-phase permanent magnet synchronous motor with the advantages of small size, light weight and high efficiency. A control module (inverter) is also required to convert direct current into alternating current to ensure stable operation of the motor while generating sufficient torque to drive the compressor.

The compressor for new energy vehicles has many advantages. First, it is more efficient and environmentally friendly, because it is driven by electric energy instead of mechanical movement of the engine, and does not produce emissions. Second, the noise is much lower than that of the compressor for traditional fuel vehicles. For example, during the driving of new energy vehicles, the interior environment is quieter, improving driving and riding comfort.

In addition, the compressor for new energy vehicles can better meet the heat dissipation needs of new energy vehicles. When heat dissipation is required for batteries, motors, main drive inverters, BMS and other components, the air conditioning compressor can participate in this part of heat dissipation. At the same time, some new energy vehicles adopt a heat pump air conditioning + PTC auxiliary system, which improves heating efficiency, reduces energy consumption and has little impact on vehicle range.

There are obvious differences between the compressor for traditional fuel vehicles and the compressor for new energy vehicles in terms of power source, working principle, structural components, advantages and disadvantages.

The compressor for traditional fuel vehicles relies on engine power, increases fuel consumption and engine load, and produces relatively high noise. The compressor for new energy vehicles is powered by batteries, which is more efficient, environmentally friendly and quiet. It can better meet the heat dissipation and heating needs of new energy vehicles, improving the overall performance and driving experience of new energy vehicles.